In recent years, smartphones, cellular phones, PHS(Personal Handyphone System) and the like mobile terminals have continued to spread into a broad range of applications. Besides basic verbal communication functionality, the data communication capabilities of these terminals have been enhanced to provide users with a variety of information services through the Internet. Particularly, a variety of service making use of current location information provided by GPS or the like (Patent Document 1).
Also, when logging in, a user has to input an ID and a password for confirming user identity to use a service. When using a plurality of services, an ID and a password have to be determined for each service, it becomes a burden on the user to keep them in mind. In this situation, an authentication provider makes it possible to use a single sign-on protocol such as OAuth, OpenID (Patent Document 2).